Abstract

is a persistent red phosphor.Thermoluminescence was measured under different excitation and thermal treatment conditions. The results reveal that the charge defects, created by substituting for serve as hole traps for the afterglow at room temperature. plays the role of deep electron trapping centers, capturing electrons either through the conduction band or directly from the excited ions. These two processes, in which two different sites of are involved, correspond to two traps with different depths.